An unknown error has occurred while validating the server
In the section labeled ## SITE/SERVER INFO: ## you should see the three items highlighted below.Solution: If JSON is marked as No, then this means that JSON isn’t running on your website server.
If your page or group is fairly new then it may not actually have an eligible posts that the plugin can display.
Notifications such as ‘__ changed the cover photo’ or ‘__ created a group’ are filtered out and aren’t displayed.
If you are familiar with editing this file then you can enable one or both of them yourself, otherwise it’s recommended that you contact your web host and request that they enable one or both of these extensions on your server.
If only one of either PHP allow_url_fopen or PHP c URL is marked as No then the plugin should still function as expected.
It is in fact against Facebook policies to use a profile to represent something other than yourself (see ‘Why should I convert my profile to a page’ in the link above).
Once you’ve converted to a page then the plugin will be able to retrieve and display all of your posts.Solution: Try increasing the post limit on the plugin’s Settings page to be 10-15 higher than the number of posts you are trying to display.The maximum post limit varies depending on how much data is associated with your posts, but it’s usually around 100.This isn’t desirable for most pages as it means that it isn’t accessible by people who don’t have a Facebook account and that your page can’t be crawled and indexed by search engines.An easy way to determine whether your page is set to public is to make sure you’re signed out of your Facebook account and then try to visit your page.If you’re using your own Access Token then the easiest way to check whether it works is to test it on the Demo page.